F. Duru et al., The potential for inappropriate ventricular tachycardia confirmation usingthe Intracardiac Electrogram (EGM) Width Criterion, PACE, 22(7), 1999, pp. 1039-1046
Citations number
12
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
The "Intracardiac Electrogram (EGM) Width Criterion," the first digital sig
nal processing feature used in an implantable cardioverter defibrillator (I
CD), is a detection enhancement algorithm that intends to improve ventricul
ar tachycardia (VT) defection specificity by rejecting inappropriately dete
cted supraventricular tachyarrhythmias. The algorithm may be activated afte
r setting the optimal EGM source, slew, and width thresholds based on EGM w
idth testing during sinus rhythm. This study evaluates the accuracy of the
EGM width measurements during exercise testing. Twenty-one patients with Me
dtronic Micro Jewel II Model 7223 ICDs underwent treadmill exercise testing
. EGM width resting was repeatedly performed during exercise and recovery t
o detect potential inappropriate measurements. In seven (33%) patients the
EGM Width Criterion inappropriately confirmed VT detection. Eleven patients
had inappropriately wide EGM width measurements, but did not satisfy the E
GM Width Criterion. The causes of wide EGM width measurements were an actua
l increase in EGM width and/or inappropriate detection of the baseline irre
gularities as EGM onset or offset points. Based on our observations, we rec
ommend to test the EGM Width Criterion during exercise testing for optimal
ICD programming.